US20010014715A1 - Aqueous barrier coating compositions containing polyurethane dispersions - Google Patents

Aqueous barrier coating compositions containing polyurethane dispersions Download PDF

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Publication number
US20010014715A1
US20010014715A1 US09/770,027 US77002701A US2001014715A1 US 20010014715 A1 US20010014715 A1 US 20010014715A1 US 77002701 A US77002701 A US 77002701A US 2001014715 A1 US2001014715 A1 US 2001014715A1
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Prior art keywords
acid
molecular weight
polyurethane
dispersion
groups
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US09/770,027
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Harald Blum
Jurgen Meixner
Heino Muller
Joachim Petzoldt
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Bayer AG
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Assigned to BAYER AKTIENGESELLSCHAFT reassignment BAYER AKTIENGESELLSCHAFT ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: MULLER, HEINO, PETZOLDT, JOACHIM, MEIXNER, JURGEN, BLUM, HARALD
Publication of US20010014715A1 publication Critical patent/US20010014715A1/en
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    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G18/00—Polymeric products of isocyanates or isothiocyanates
    • C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
    • C08G18/70—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the isocyanates or isothiocyanates used
    • C08G18/72—Polyisocyanates or polyisothiocyanates
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G18/00—Polymeric products of isocyanates or isothiocyanates
    • C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
    • C08G18/08—Processes
    • C08G18/10—Prepolymer processes involving reaction of isocyanates or isothiocyanates with compounds having active hydrogen in a first reaction step
    • C08G18/12—Prepolymer processes involving reaction of isocyanates or isothiocyanates with compounds having active hydrogen in a first reaction step using two or more compounds having active hydrogen in the first polymerisation step
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G18/00—Polymeric products of isocyanates or isothiocyanates
    • C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
    • C08G18/08—Processes
    • C08G18/0804—Manufacture of polymers containing ionic or ionogenic groups
    • C08G18/0819—Manufacture of polymers containing ionic or ionogenic groups containing anionic or anionogenic groups
    • C08G18/0823—Manufacture of polymers containing ionic or ionogenic groups containing anionic or anionogenic groups containing carboxylate salt groups or groups forming them
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G18/00—Polymeric products of isocyanates or isothiocyanates
    • C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
    • C08G18/28—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
    • C08G18/40—High-molecular-weight compounds
    • C08G18/42—Polycondensates having carboxylic or carbonic ester groups in the main chain
    • C08G18/44—Polycarbonates
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G18/00—Polymeric products of isocyanates or isothiocyanates
    • C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
    • C08G18/28—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
    • C08G18/65—Low-molecular-weight compounds having active hydrogen with high-molecular-weight compounds having active hydrogen
    • C08G18/66—Compounds of groups C08G18/42, C08G18/48, or C08G18/52
    • C08G18/6633—Compounds of group C08G18/42
    • C08G18/6659—Compounds of group C08G18/42 with compounds of group C08G18/34
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
    • C09D175/00—Coating compositions based on polyureas or polyurethanes; Coating compositions based on derivatives of such polymers
    • C09D175/04—Polyurethanes
    • C09D175/06—Polyurethanes from polyesters

Definitions

  • the invention relates to novel polyurethane dispersions, a process for their production and their use in aqueous binders for rapidly drying coating compositions in automotive painting.
  • a coat to protect against impact from flying stones and a filler coat or a combination of both (“filler protecting against impact from flying stones”) is/are initially applied to a metal surface primed by cathodic electrophoretic coating (CEC). After that a pigmented base coat and then a clear top coat is applied or, alternatively, a pigmented top coat is applied.
  • CEC cathodic electrophoretic coating
  • the filler coat protecting against impact from flying stones serves to smooth out unevenness in the surface and produces a good resistance to impact from flying stones through its high elasticity and deformability.
  • Polyesters and polyurethanes as well as polyisocyanate or melamine crosslinking agents have previously been used for this coat.
  • the filler protecting against impact from flying stones is stoved prior to the application of the base coat and the clear lacquer or top coat. This is necessary to improve the “take” of the top coat and to seal any defects still present in the filler coat. Further stoving then takes place after the application of the clear lacquer or top coat. This process has the disadvantage that two expensive stoving operations are required.
  • Known coatings that dry rapidly without a stoving operation such as those containing polyacrylates, do not exhibit the required resistance to impact from flying stones, since on curing they lead to films with inadequate mechanical properties.
  • An object of the present invention is to provide a binder for a barrier coat that protects against impact from flying stones and additionally dries very rapidly such that the resulting coating has very good water-resistance and is resistant to being dissolved by the subsequently applied base or top coat. It is an additional object of the present invention that the adhesion or inter-layer adhesion should also be exceptional, in order to ensure an optimum multi-layer coating. It is a further object of the present invention for the binder to provide a light-fast, weather-resistant coating for those instances when moderately opaque top or base coats are used or when a pigmented top or base coat is completely omitted. It is a final object of the present invention for the binder to have outstanding stability, in particular viscosity stability, when formulated in coating compositions and the ability to be repaired directly on the coating line.
  • EP-A-0 498 156 describes polyester dispersions containing urethane groups, which are very suitable for producing intermediate primer coats protecting against impact from flying stones or stoving fillers with high resistance to impact from flying stones. In order to achieve these superior properties, however, high curing temperatures or long stoving times are required.
  • DE-A-3,936,794 describes polyurethane dispersions containing carbonate groups and their use in automotive painting, e.g. for base coats. Stoving conditions of approx. 140° C. and, in cases of repair on the line, curing at approx. 80° C. are mentioned. Important requirements for these dispersions are e.g. adhesion, weathering resistance and resistance to condensation also at 80° C. drying.
  • DE-A-4,438,504 describes coating compositions based on water-thinnable polyurethane resins with a number average molecular weight (Mn) of 4000 to 25000 g/mole.
  • Mn number average molecular weight
  • the present invention relates to aqueous polyurethane dispersions wherein the polyurethanes are reaction products of
  • the neutralizing agent is added in an amount sufficient to neutralize 40 to 105% of the acid groups and an amount sufficient to neutralize at least 60% of the acid groups is added prior to the chain extension reaction,
  • the polyurethane contains 1 to 4 wt. % of the urea groups set forth in brackets in the following formula:
  • the present invention also relates to a process for preparing these polyurethane dispersions which comprises forming an isocyanate- and acid-functional polyurethane by reacting
  • the present invention additionally relates to coating compositions containing these polyurethane dispersions.
  • Suitable components A) include at least difunctional polyesters, polyethers, polyether polyamines, polycarbonates and polyester amides having a number average molecular weight of 500 to 6000.
  • polyesters prepared from dicarboxylic acids or their anhydrides e.g.
  • adipic acid succinic acid, phthalic acid anhydride, isophthalic acid, terephthalic acid, suberic acid, azelaic acid, sebacic acid, tetrahydrophthalic acid, maleic anhydride, dimeric fatty acids and diols, e.g., ethylene glycol, propylene glycol, 1,3-propanediol, diethylene glycol, triethylene glycol, 1,4-butanediol, 1,6-hexanediol, trimethylpentanediol, 1,4-cyclo-hexanediol, 1,4-cyclohexane-dimethanol, neopentyl glycol and 1,8-octanediol.
  • dimeric fatty acids and diols e.g., ethylene glycol, propylene glycol, 1,3-propanediol, diethylene glycol, triethylene glycol, 1,4-butan
  • the polyesters can also be prepared from mono-, tri- or tetrafunctional raw materials, such as 2-ethylhexanoic acid, benzoic acid, soya bean oil fatty acid, oleic acid, stearic fatty acid, sunflower oil fatty acid, trimellitic anhydride, trimethylol propane, glycerine and pentaerythritol.
  • mono-, tri- or tetrafunctional raw materials such as 2-ethylhexanoic acid, benzoic acid, soya bean oil fatty acid, oleic acid, stearic fatty acid, sunflower oil fatty acid, trimellitic anhydride, trimethylol propane, glycerine and pentaerythritol.
  • polyesters made from lactones, in particular ⁇ -caprolactone; polycarbonates, available by reacting for example of the diols mentioned above with diaryl or dialkyl carbonates or phosgene; and castor oil.
  • polyethers such as can be obtained by the polymerization of propylene oxide and/or tetrahydrofuran, optionally with the additional use of small amounts of ethylene oxide and/or styrene oxide wherein diols, triols, water or amines are used as starter molecule(s).
  • Preferred components A) are difunctional polyesters having a number average molecular weight of 840 to 2600, preferably 1700 to 2100, which are prepared from aliphatic raw materials, such as adipic acid, maleic anhydride, hexanediol, neopentyl glycol, ethylene glycol, propylene glycol and diethylene glycol, more preferably adipic acid, hexanediol and neopentyl glycol.
  • aliphatic raw materials such as adipic acid, maleic anhydride, hexanediol, neopentyl glycol, ethylene glycol, propylene glycol and diethylene glycol, more preferably adipic acid, hexanediol and neopentyl glycol.
  • Preferred components A) are also aliphatic polycarbonate diols or polyester carbonate diols having a number average molecular weight of 840 to 2600.
  • component A) contains a mixture of 20 to 80 wt. % of an aliphatic polyester diol with a number average molecular weight of 840 to 2100 and 20 to 80 wt. % of an aliphatic polycarbonate diol or polyester carbonate diol with a number average molecular weight of 1000 to 2100.
  • polyester diols are used alone, it is advantageous for good water resistance and resistance to hydrolysis to select particular polyester diols, e.g. those based on adipic acid, hexanediol, neopentyl glycol and having a molecular weight of 1700 to 2100.
  • polycarbonate diols alone can lead to problems in the film appearance, e.g. due to non-optimal flow, and in unfavorable conditions also to non-optimal inter-layer adhesion.
  • Suitable low molecular weight components B) have a number average molecular weight of less than 500, preferably 62 to 400, and include ethylene glycol, 1,4-butanediol, 1,6-hexanediol, neopentyl glycol, trimethylol propane, glycerine, pentaerythritol, trimethyl-pentanediol, propylene glycol, 1,3-propanediol, 1,4-cyclohexadimethanol, or their reaction products with ethylene and/or propylene oxide.
  • component B) is a tri- or higher-functional low molecular weight alcohol such as trimethylol propane, glycerine, pentaerythritol or their reaction products with 1 to 6 moles of ethylene and/or propylene oxide.
  • trifunctional alcohols such as trimethylol propane or glycerin in an amount of 0.5 to 4.0, preferably 1.0 to 3.0 wt. %.
  • Suitable components C) include di- and/or trifunctional aliphatic isocyanates such as hexamethylene diisocyanate, butane diisocyanate, isophorone diisocyanate, 1-methyl-2,4- and/or 2,6-diisocyanatocyclo-hexane, norbornane diisocyanate, xylylene diisocyanate, tetramethyl xylylene diisocyanate, hexahydro xylylene diisocyanate, nonane triisocyanate and 4,4′-diisocyanatodicyclohexylmethane.
  • di- and/or trifunctional aliphatic isocyanates such as hexamethylene diisocyanate, butane diisocyanate, isophorone diisocyanate, 1-methyl-2,4- and/or 2,6-diisocyanatocyclo-hexane, norbornane diisocyanate, xy
  • aromatic isocyanates such as 2,4- and/or 2,6-diisocyanatotoluene or 4,4′-diisocyanato-diphenylmethane, as well as higher molecular weight or oligomeric polyisocyanates having a number average molecular weight of 336 to 1500 and based on the above-mentioned aliphatic isocyanates.
  • preferred components C) results in the production of high quality polyurethane dispersions for barrier coats having an exceptional level of protection against impact from flying stones.
  • Component D) is selected from (potentially) ionic compounds having at least one acid group and at least one hydroxyl and/or amino group, which is reactive to isocyanate groups.
  • these compounds contain at least one carboxylic acid group and one or two hydroxyl and/or amino groups.
  • Suitable acids include 2,2-bis(hydroxymethyl)alkanecarboxylic acids (such as dimethylol acetic acid, 2,2-dimethylol propionic acid, 2,2-dimethylol butyric acid or 2,2-dimethylol-pentane acid), dihydroxy-succinic acid, hydroxypivalic acid or mixtures of such acids.
  • dimethylol propionic acid and/or hydroxypivalic acid is used as component D).
  • sulfonic acid diols optionally containing ether groups as described in U.S. Pat. No. 4,108,814.
  • the free acid groups represent the above-mentioned “potentially ionic” groups, while the salt groups obtained by neutralizing the acid groups with neutralizing agents are “ionic” groups.
  • Component D) is used in amounts sufficient to provide an acid number, based on resin solids, ⁇ 25, preferably ⁇ 20 mg/KOH g of substance.
  • the dispersions may also be prepared from less than 4 wt. % of component E), which is selected from nonionic-hydrophilic polyethers containing one or two isocyanate-reactive groups, preferably hydroxyl groups, and preferably having a number-average molecular weight of 350 to 2500.
  • component E is selected from nonionic-hydrophilic polyethers containing one or two isocyanate-reactive groups, preferably hydroxyl groups, and preferably having a number-average molecular weight of 350 to 2500.
  • aqueous polyurethane dispersions according to the invention are preferably reaction products of
  • the neutralizing agent is added in an amount sufficient to neutralize 60 to 105% of the acid groups and an amount sufficient to neutralize at least 60% of the acid groups is added prior to the chain extension reaction,
  • the polyurethane contains 1 to 4, preferably 1.75 to 3.25 wt. % of the urea groups set forth in brackets in formula I.
  • the calculation of the urea group content is based on the assumption that half of the isocyanate groups of the polyurethane prepolymer react with water to form amino groups (accompanied by CO 2 formation), which then react with the other half of the isocyanate groups to form isolated monourea bridges, which increases the molecular weight.
  • aqueous polyurethane dispersions according to the invention are reaction products of
  • reaction of hydroxy-functional components A), B), D) and optionally E) with the isocyanate component C) takes place in known manner in one or more stages, wherein the quantitative ratios of the reactants are selected such that the equivalent ratio of NCO:OH groups is 2.5:1 to 1.2:1, preferably 1.7:1 to 1.4:1.
  • the reaction can be carried out with the addition of small amounts of catalysts, such as dibutyltin dilaurate, tin-2-octoate, dibutyltin oxide or diazabicyclononane.
  • the reaction is preferably carried out in a 35 to 97% organic solution, more preferably in a 55 to 75% acetone solution.
  • a preferred process for preparing the polyurethane dispersion of the invention comprises forming an isocyanate- and acid-functional polyurethane by reacting
  • neutralizing agent Prior to the dispersing of the organically dissolved, isocyanate-functional polyurethane prepolymer, or else already prior to the reacting of components A), B), D), and optionally E) with the isocyanate-functional component C), neutralizing agent is added in an amount sufficient to neutralize 40% to 105%, preferably 50% to 105% of the acid groups. It is also possible to add the neutralizing agent to the dispersing water.
  • Preferred neutralizing agents include triethylamine, N-methyl morpholine, dimethyl-isopropylamine, diisopropylaminoethanol, dimethyl ethanolamine and dimethyl isopropanolamine. Mixtures of different neutralizing agents can also be used. Ammonia is also suitable as a neutralizing agent in certain cases. Particularly preferred is diethyl isopropylamine, optionally in admixture with other amines.
  • the solvents used to produce the polyurethane prepolymer can be partially or preferably completely separated out of the dispersion by distillation.
  • the dispersions according to the invention contain less than 2.5 wt. % and more preferably do not contain organic solvent.
  • chain extension of the isocyanate-functional polyurethane prepolymer in water can optionally be added to react with up to 40% of the isocyanate groups present. They can optionally also contain ionic groups, acid groups or hydroxyl groups. Preferably, however, chain extension is carried out exclusively via the isocyanate-water reaction.
  • the dispersions according to the invention have particle diameters, determined e.g. by LKS measurements, of 20 to 600, preferably of 50 to 150 nm.
  • the solids content of the dispersions is at least 30%, preferably at least 35%.
  • the pH value of the dispersion is less than 8.5, preferably below 7.8.
  • the number average molecular weight (Mn) of the dispersion is >20,000, preferably >30,000 and more preferably >40,000 g/mole (as determined by gel permeation chromatography).
  • Mn number average molecular weight
  • a portion of the dispersion contains very high molecular weight portions, which are no longer completely soluble in organic solvents and for which molecular weight cannot be determined.
  • the products according to the invention are suitable for coating any substrates, in particular wood, ceramics, stone, concrete, bitumen, hard fiber, glass, china, plastics and metal undersurfaces.
  • substrates in particular wood, ceramics, stone, concrete, bitumen, hard fiber, glass, china, plastics and metal undersurfaces.
  • they can be used as a finish or dressing in textile or leather coating.
  • the preferred field of use is the initial coating of vehicles, in particular as a barrier coat to obtain high level of protection against impact from flying stones and exceptional water resistance.
  • the dispersions according to the invention can also contain known additives, e.g., inorganic or organic pigments, fillers (such as carbon black, silica, talc, chalk, siliceous earth and kaolin), glass in the form of powder or fibers, and cellulose or cellulose acetate butyrate.
  • the dispersions can also contain crosslinking agents such as blocked polyisocyanates, polyisocyanates, melamine resins, urea resins, urea-aldehyde resins, carbodiimides, carbamates, tris(alkoxycarbonylamino)-triazines and carbamate-modified amino-crosslinking resins.
  • the crosslinking agents can be used in water-dispersible or in non-water-dispersible (hydrophobic) form.
  • polyisocyanates which may be blocked, include cycloaliphatic or aliphatic polyisocyanates such as hexamethylene diisocyanate (HDI), 1-iso-cyanato-3,3,5-trimethyl-5-isocyanatomethylcyclo-hexane (isophorone diisocyanate, IPDI), methylene-bis-(4-isocyanato-cyclohexane) and tetramethyl xylylene diisocyanate (TMXDI).
  • cycloaliphatic or aliphatic polyisocyanates such as hexamethylene diisocyanate (HDI), 1-iso-cyanato-3,3,5-trimethyl-5-isocyanatomethylcyclo-hexane (isophorone diisocyanate, IPDI), methylene-bis-(4-isocyanato-cyclohexane) and tetramethyl xylylene diisocyanate (TMXDI).
  • polyisocyanates are the known prepolymers containing terminal isocyanate groups and obtained in particular by reacting the above-mentioned monomeric polyisocyanates, in particular diisocyanates, with less than equivalent amounts of organic compounds having at least two isocyanate-reactive groups, preferably the polyols previously described.
  • Suitable blocking agents for preparing the blocked polyisocyanates include dimethyl malonate, diethyl malonate, ethyl acetoacetate, caprolactam, secondary aliphatic amines, butanone oxime and 3,5-dimethyl pyrazole.
  • the blocked polyisocyanates can be used in hydrophobic form, wherein the transfer into the aqueous dispersion can be obtained, e.g., by mixing and joint dispersion with the polyurethane prepolymer.
  • the polyurethane dispersion according to the invention can also be used as a polymeric emulsifier for non-water-dispersible crosslinking agents. It is also possible to add to the polyurethane dispersion according to the invention a hydrophilic blocked polyisocyanate that is water-dispersible or already present in water-dispersible form. Hydrophilic blocked polyisocyanates are known and described, e.g., in EP-A-0 566 953 (U.S. Pat. No. 5,455,297, herein incorporated by reference).
  • Preferred crosslinking agents are reactive amino-crosslinking resins or melamine resins such as Cymel 328 (Cytec); trisalkoxycarbonyl-aminotriazines such as TACT (Cytec); and/or reactive malonic ester-blocked polyisocyanate crosslinking agents and/or urethanized melamine resins.
  • reactive amino-crosslinking resins or melamine resins such as Cymel 328 (Cytec); trisalkoxycarbonyl-aminotriazines such as TACT (Cytec); and/or reactive malonic ester-blocked polyisocyanate crosslinking agents and/or urethanized melamine resins.
  • polyurethane dispersions according to the invention can be combined with other binders. Preferred is the combination with water-soluble or water insoluble melamine resins as well as water-emulsifiable or water dispersible polyester resins or polyester-polyurethane resins.
  • the handling of the dispersion for producing coatings can take place according to any method known in the art, for example by brushing, pouring, spraying, dipping, rolling or knife coating.
  • the dispersions according to the invention are suitable for producing coating compositions, sealants and adhesives.
  • the drying of the products obtained by various application techniques can take place at room temperature or at elevated temperatures of up to 200° C., preferably at 60 to 150° C.
  • the application preferably takes place by spraying and drying preferably for 5 to 10 minutes at 50 to 80° C.
  • the dry film coating thickness is preferably between 15 and 50 ⁇ m, but coatings with higher coating thicknesses are possible.
  • the coating can be adjusted to be highly flexible, but also hard, depending upon the requirements.
  • After drying the barrier coat is sandable and very easy to overcoat.
  • the resulting coating has optical and mechanical properties that are comparable to or better than a multi-layer coating in which, instead of the barrier coat, a filler is applied in known manner at a 35 to 45 ⁇ m dry film coating thickness and individually stoved for 20 to 25 minutes at 135 to 165° C., and subsequently a base coat/clear coat or pigmented top coat is applied.
  • the dispersions according to the invention can be mixed with other ionic or nonionic dispersions or aqueous dispersions, e.g., with polyester-polyvinyl acetate, polyethylene, polystyrene, polybutadiene, polyurethane, polyvinyl chloride, polyester-polyacrylate, polyacrylate and copolymer dispersions or solutions.
  • ionic or nonionic dispersions or aqueous dispersions e.g., with polyester-polyvinyl acetate, polyethylene, polystyrene, polybutadiene, polyurethane, polyvinyl chloride, polyester-polyacrylate, polyacrylate and copolymer dispersions or solutions.
  • polyester-polyvinyl acetate polyethylene
  • polystyrene polybutadiene
  • polyurethane polyvinyl chloride
  • polyester-polyacrylate polyacrylate
  • copolymer dispersions or solutions e.g., poly
  • Preferred is the use of water-soluble or water-dispersible polyesters, polyester-polyurethanes, polyester-polyacrylates as well as other polyurethane dispersions, in particular of polyurethane dispersions with rapid natural drying and high rigid segment contents.
  • the coating compositions for barrier coats contain in addition to the known additives used in automotive coatings and optionally water for adjusting the spraying consistency
  • the coating compositions for barrier coats have solids contents of at least 45, preferably at least 50% with application consistency and also exhibit a very good stability to viscosity during storage in the presence of highly reactive crosslinking agents for stoving compositions, e.g. melamine resins.
  • barrier coats prepared from the dispersions according to the invention have an outstanding resistance to impact from flying stones and very good adhesion and intercoat adhesion.
  • the polyurethane dispersions according to the invention can also be used to produce reactive stoving compositions curable at low temperatures, in particular stoving fillers. They are preferably combined with reactive crosslinking resins and optionally other polymers such that coatings are obtained at 90 to 120° C. optionally with the additional use of suitable catalysts and known pigments and additives.
  • a polyester dispersion containing urethane groups was prepared according to EP-A-0 498 156 (U.S. Pat. No. 5,280,062), Example 2; solids content approx. 41%, viscosity approx. 1000 mPa.s/23° C.
  • a paint for a barrier coat 3 was produced from 117 g of pigment paste A), 182 g of dispersion 1), 9.8 g of an amino-crosslinking resin (Cymel 328, Cytec) and 10 g of distilled water.
  • the coating composition had a pH of 7.6, a solids content of 52% and a flow time in ISO 5 cup of 21 seconds. After storage for 14 days at room temperature the viscosity of the coating composition had increased only slightly (24 seconds).
  • Pigment paste A was produced from the following raw materials by grinding on a pearl mill: 42.2 g of a water dispersible polyester resin (Bayhydrol D270, dissolved 70% in organic solvents, Bayer), 82.4 g distilled water, 6 g of a 10% aqueous solution of dimethyl ethanolamine, 5.4 g of a 50% solution of a wetting agent (Surfynol 104, Air Products) in NMP, 5.4 g of an additive (Additol XW 395), 108.2 g of titanium dioxide (Bayertitan R-FD, Bayer), 1.2 g of iron oxide (Bayferrox 303T, Bayer), 108.9 g of an additive (Blanc fixe micro, Sachtleben), 26.6 g of talc (Talkum IT extra, Norwegian Talk) and 3.7 g of an additive (Aerosil R 972, Degussa).
  • a water dispersible polyester resin Boyhydrol D270,
  • CEC cathodic electrodeposition coating
  • barrier coat 3 20 ⁇ m dry film thickness, 10 minutes 70° C. surface drying,
  • Intercoat adhesion barrier coat/top coat (marks from 1 to 3, 1—very good, 3—poor): 1
  • Solvent resistance incipient solubility test with one minute of exposure to the following solvents: toluene, methoxypropyl acetate, ethyl acetate, acetone, rating 0 to 5, 0—unchanged, 5—dissolved: 2/2/2/2
  • Dispersion 1) meets all of the requirements needed for a barrier coat.
  • a paint for a barrier coat was produced with the use of comparison dispersion 2) instead of dispersion 1), corresponding coatings were applied and cured, and the properties were tested.
  • the comparison product was unsuitable as a barrier coat. Also, the solvent resistance and in particular the film hardness and the water resistance were inadequate.
  • Heating was carried out until the isocyanate content was at or below the theoretical isocyanate value.
  • 5.8 g of ethylene diamine diluted with 30 g water were added within 5 minutes, which corresponded to a degree of chain extension of approx. 60% (i.e. sufficient reactive amino groups in the form of a diamine were added to react with approx. 60% of the isocyanate groups still remaining).
  • After stirring for 15 minutes 10.0 g triethylamine (degree of neutralization 75%) and thereafter 5500 g of distilled water were added. Stirring was carried out at 40 to 50° C. until free isocyanate groups were no longer detected. The acetone was then removed by distillation.
  • a finely divided dispersion 5 having a solids content of 32%, a pH of 7.8 and a viscosity of approx. 1100 mPa.s/23° C. was obtained.
  • Example 3 As described in Example 3), a coating composition for a barrier coat was produced with the use of comparison dispersion 5) instead of dispersion 1), coatings were applied and cured, and the properties were tested.
  • a paint for a barrier coat was produced with the use of comparison dispersion 7) instead of dispersion 1), coatings were applied and cured, and the properties were tested.
  • the comparison coating composition was unsuitable as a barrier coat, since neither a homogeneous multi-layer coating was achieved and the film hardness and water resistance was inadequate.
  • a coating composition for a barrier coat 10) was produced from 117 g of a pigment paste A), 195 g of dispersion 9), 9.8 g of an amino-crosslinking resin (Cymel 328, Cytec) and 8 g of distilled water.
  • the paint had a pH of 7.5, a solids content of 50.3% and a flow time in an ISO 5 cup of 21 seconds. After storage for 14 days at room temperature the viscosity of the coating composition increased only slightly (27 seconds).
  • Dispersion 9 meets all the requirements for a barrier coat.
  • a paint for a barrier coat 12 was produced from 117 g of a pigment paste A) , 195 g of dispersion 11), 9.8 g of amino-crosslinking resin (® Cymel 328, Cytec) and 8 g of distilled water.
  • the paint had a pH value of 7.4, a solids content of 50.5% and a flow time in the ISO 5 cup of 16 seconds. After 14 days' storage of the paint at room temperature the viscosity had increased only slightly (18 seconds).
  • Inter-layer adhesion barrier coat/top coat (marks from 1 to 3, 1 is very good, 3 is poor): 1
  • Interlayer adhesion barrier coat/CEC (marks from 1 to 3, 1 is very good, 3 is poor): 1
  • Dispersion 11 meets all the requirements.
  • a paint for a barrier coat 10 was produced from 117 g of a pigment paste A), 209 g of the dispersion 13), 9.8 g of amino-crosslinking resin (Cymel® 328, Cytec) and 8 g of distilled water.
  • the paint had a pH value of 7.5, a solids content of approx. 49% and a flow time in the ISO 5 cup of 15 seconds. After 14 days' storage of the paint at room temperature the viscosity had increased only slightly (17 seconds).
  • Inter-layer adhesion barrier coat/top coat (marks from 1 to 3, 1 is very good, 3 is poor): 1
  • Interlayer adhesion barrier coat/CEC (marks from 1 to 3, 1 is very good, 3 is poor): 1
  • Dispersion 13 meets all the requirements, however because of the reduced content of dimethylolpropionic acid the film hardness is in the lower range of the acceptable values.

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Medicinal Chemistry (AREA)
  • Polymers & Plastics (AREA)
  • Health & Medical Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Materials Engineering (AREA)
  • Wood Science & Technology (AREA)
  • Manufacturing & Machinery (AREA)
  • Paints Or Removers (AREA)
  • Polyurethanes Or Polyureas (AREA)
  • Organic Insulating Materials (AREA)
US09/770,027 2000-02-03 2001-01-25 Aqueous barrier coating compositions containing polyurethane dispersions Abandoned US20010014715A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE10004723.8 2000-02-03
DE10004723A DE10004723A1 (de) 2000-02-03 2000-02-03 Wässrige Sperrschicht auf Basis von Polyurethan-Disperionen

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US (1) US20010014715A1 (cs)
EP (1) EP1122269A1 (cs)
JP (1) JP2001213933A (cs)
KR (1) KR20010078182A (cs)
BR (1) BR0100314A (cs)
CA (1) CA2333443A1 (cs)
CZ (1) CZ2001417A3 (cs)
DE (1) DE10004723A1 (cs)
MX (1) MXPA01001313A (cs)
PL (1) PL345529A1 (cs)
SK (1) SK1642001A3 (cs)

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US20020107336A1 (en) * 2000-09-25 2002-08-08 Joachim Petzoldt Low temperature-drying waterborne coatings
US20040204559A1 (en) * 2002-11-07 2004-10-14 Martin Melchiors Polyurethane resin with high carbonate group content
US20060290901A1 (en) * 2005-06-23 2006-12-28 Cam Co., Ltd. Light shielding heat-resistant sheet material, and light amount regulating apparatus and projector apparatus utilizing the same
US20100273939A1 (en) * 2007-12-26 2010-10-28 Friederike Stollmaier Polyurethane dispersions and coatings produced therefrom
US8361273B2 (en) 2006-07-08 2013-01-29 Ferring B.V. Polyurethane elastomers
US8460707B2 (en) 2004-08-05 2013-06-11 Ferring B.V. Stabilised prostaglandin composition
US8524254B2 (en) 2006-10-18 2013-09-03 Ferring B.V. Bioresorbable polymers
US8557281B2 (en) 2002-09-27 2013-10-15 Ferring B.V. Water-swellable polymers
US8974813B2 (en) 2006-07-05 2015-03-10 Ferring B.V. Hydrophilic polyurethane compositions
CN104966847A (zh) * 2015-05-06 2015-10-07 深圳高远通新材料科技有限公司 一种高锂盐浓度的水性聚氨酯离聚体的制备方法及应用
JP2016017157A (ja) * 2014-07-09 2016-02-01 旭化成ケミカルズ株式会社 ポリイソシアネート組成物
CN106243317A (zh) * 2016-07-28 2016-12-21 上海维凯光电新材料有限公司 基于丙酮法的水性聚氨酯合成方法
US20210253775A1 (en) * 2018-05-14 2021-08-19 Dainichiseika Color & Chemicals Mfg. Co., Ltd. Aqueous polyurethane resin dispersion and method for producing same, paint, film arrangement, and structure

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DE10114872A1 (de) * 2001-03-22 2002-09-26 Volkswagen Ag Kunststoffhohlkörper mit Sperrschicht gegen Permeation
DE10155184A1 (de) * 2001-11-12 2003-05-22 Bayer Ag Emulsionspolymerisate als Abziehlack
AT411062B (de) * 2001-11-19 2003-09-25 Solutia Austria Gmbh Beschichtungsmittel
WO2008077766A1 (de) * 2006-12-22 2008-07-03 Basf Se Mikrokapseln, enthaltend verbindungen mit carbodiimidgruppen
CN109096468A (zh) * 2018-09-11 2018-12-28 洛阳盛嘉新材料有限公司 一种无溶剂水性聚氨酯树脂及其制备方法
CN109627417A (zh) * 2018-10-25 2019-04-16 湖南湘江关西涂料有限公司 一种水性抗石击聚氨酯分散体及其制备方法

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JPH01193367A (ja) * 1988-01-27 1989-08-03 Sanyo Chem Ind Ltd 金属用水系焼付け塗料組成物
DE4216536A1 (de) * 1992-05-19 1993-11-25 Bayer Ag Wasserverdünnbare Polyesterpolyole und ihre Verwendung
DE4224617A1 (de) * 1992-07-25 1994-01-27 Herberts Gmbh Wäßriges Überzugsmittel, Verfahren zu dessen Herstellung und dessen Verwendung bei Verfahren zur Mehrschichtlackierung
DE4308079A1 (de) * 1993-03-13 1994-09-15 Basf Ag Verwendung von wäßrigen Polyurethandispersionen als Verbundfolienklebstoff
DE19630905A1 (de) * 1996-08-01 1998-02-05 Wolff Walsrode Ag Wäßrige Dispersionen, ihre Herstellung und Verwendung als Lackbindemittel
DE19824484A1 (de) * 1998-06-02 1999-12-09 Bayer Ag Festkörperreiche Polyurethandispersionen mit hoher Applikationssicherheit

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US6827983B2 (en) 2000-09-25 2004-12-07 Bayer Aktiengesellschaft Low temperature-drying waterborne coatings
US20020107336A1 (en) * 2000-09-25 2002-08-08 Joachim Petzoldt Low temperature-drying waterborne coatings
US8557281B2 (en) 2002-09-27 2013-10-15 Ferring B.V. Water-swellable polymers
US9987364B2 (en) 2002-09-27 2018-06-05 Ferring B.V. Water-swellable polymers
US8628798B2 (en) 2002-09-27 2014-01-14 Ferring B.V. Water-swellable polymers
US20040204559A1 (en) * 2002-11-07 2004-10-14 Martin Melchiors Polyurethane resin with high carbonate group content
US6927254B2 (en) 2002-11-07 2005-08-09 Bayer Aktiengesellschaft Polyurethane resin with high carbonate group content
US8709482B2 (en) 2004-08-05 2014-04-29 Ferring B.V. Stabilised prostaglandin composition
US8460707B2 (en) 2004-08-05 2013-06-11 Ferring B.V. Stabilised prostaglandin composition
US8491934B2 (en) 2004-08-05 2013-07-23 Ferring B.V. Stabilised prostaglandin composition
US20060290901A1 (en) * 2005-06-23 2006-12-28 Cam Co., Ltd. Light shielding heat-resistant sheet material, and light amount regulating apparatus and projector apparatus utilizing the same
US8974813B2 (en) 2006-07-05 2015-03-10 Ferring B.V. Hydrophilic polyurethane compositions
US10105445B2 (en) 2006-07-05 2018-10-23 Ferring B.V. Hydrophilic polyurethane compositions
US8361273B2 (en) 2006-07-08 2013-01-29 Ferring B.V. Polyurethane elastomers
US8361272B2 (en) 2006-07-08 2013-01-29 Ferring B.V. Polyurethane elastomers
US8524254B2 (en) 2006-10-18 2013-09-03 Ferring B.V. Bioresorbable polymers
CN101959914A (zh) * 2007-12-26 2011-01-26 陶氏环球技术公司 聚氨酯分散体和从该分散体制得的涂层
US20100273939A1 (en) * 2007-12-26 2010-10-28 Friederike Stollmaier Polyurethane dispersions and coatings produced therefrom
US8362142B2 (en) 2007-12-26 2013-01-29 Dow Global Technologies Llc Polyurethane dispersions and coatings produced therefrom
JP2016017157A (ja) * 2014-07-09 2016-02-01 旭化成ケミカルズ株式会社 ポリイソシアネート組成物
CN104966847A (zh) * 2015-05-06 2015-10-07 深圳高远通新材料科技有限公司 一种高锂盐浓度的水性聚氨酯离聚体的制备方法及应用
CN106243317A (zh) * 2016-07-28 2016-12-21 上海维凯光电新材料有限公司 基于丙酮法的水性聚氨酯合成方法
US20210253775A1 (en) * 2018-05-14 2021-08-19 Dainichiseika Color & Chemicals Mfg. Co., Ltd. Aqueous polyurethane resin dispersion and method for producing same, paint, film arrangement, and structure

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PL345529A1 (en) 2001-08-13
EP1122269A1 (de) 2001-08-08
JP2001213933A (ja) 2001-08-07
CZ2001417A3 (cs) 2001-09-12
KR20010078182A (ko) 2001-08-20
BR0100314A (pt) 2001-10-09
DE10004723A1 (de) 2001-08-09
SK1642001A3 (en) 2002-06-04
MXPA01001313A (es) 2002-08-06
CA2333443A1 (en) 2001-08-03

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